In devices such as compressors it is common to have the motor, as well as the pump structure, in a semi-hermetic casing or housing with the motor supported by straddled bearings. The motor structure must be accurately located with respect to the pump structure for proper operation and to avoid undue stress and wear. Conventional assemblies of this type use, for example, locating features such as dowel pins to make the critical alignment of the housing components. This adds critical features to the machining and inspection process. It also increases capital costs for machining and inspection.